How make symbolic variables to a power equal to zero

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Wojciech Kalinowski 2021-5-22

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回答： Paul 2021-5-24

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Hi,

I'm calculating inertia using thin strucuter theory. I have all of my components of inertial set as an symbolic array.

for example:

Iy_ = [16*t^3 / a, a^2 * t]

However, I need to equate any element in the array to 0 if the variable t is to an power greater than 1. So t^2, t^3, ... would equal zero where as t would remain as t.

Is there any convineint way to do this in MATLAB 2020a?

Thanks in advanced.

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Answer 1

Uday Pradhan 2021-5-24

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Hello,

I believe the below information will be helpful:

syms t;
sympol = 10 * t^2; 
deg = numel(sym2poly(sympol)) - 1; %sym2poly extracts vector of all numeric coefficients, including zeros, from symbolic polynomial
if deg > 1
    % evaluate sympol to 0
end